This invention relates to a method for reducing the toxic side effects of cancer therapy. More particularly this invention relates to the use of interferon administered in a form adapted to promote contact with the inside of a patient's mouth and pharynx to reduce the undesirable side effects resulting from the administration of radiotherapy and chemotherapeutic agents during the treatment of cancer.
Treatment of cancer has, over the last twenty years, been the focus of a significant research and development effort. Many approaches to cancer therapy have been investigated. As a practical matter, cancer therapy can involve use of multiple treatment methods including surgical excision, radiation therapy (radiotherapy), chemotherapy, and bone marrow transplantation (for treatment in patients with some types of hematological malignancies, particularly acute myelocytic leukemia). The specific protocol utilized to treat a given malignancy, depends on the nature, location and type of malignancy being treated. Surgical excision is the preferred method for treatment of primary circumscribed tumors. Often, however, surgical excision is combined with radiation therapy and/or chemotherapy to complete the treatment protocol. In instances where the malignancy is not localized or where its location lowers the probability of successful removal or excision by surgical techniques, chemotherapy and radiation therapy are often used in combination.
Chemotherapy has been shown to produce long term remissions in patients with some types of cancer, including Hodgkin's Disease, acute lymphocytic and myelogenous leukemia, testicular cancer and non-Hodgkin's lymphoma. In other types of cancer, chemotherapY has been used successfully to decrease the size of large primary tumors prior to surgery. Chemotherapy often involves the use of combinations of chemotherapeutic agents. New protocols (programs for combination drug treatment) are being developed and tested continuously by the medical research community.
Anti-tumor agents are drugs which, in addition to killing tumor cells, can and do damage normal tissue. Even with the extensive research that has been conducted to define dosage levels and scheduling of drug administration, chemotherapy often results in unpleasant and possiblY dangerous side effects due to drug toxicity. Radiation therapy produces many of the same problems. Most common of such side effects are nausea and vomiting, alopecia (hair loss), and bone marrow depression. Such side effects are usually, but not always, reversible. Some anti-cancer drugs may permanently damage the nervous system, heart, lungs, liver, kidneys, gonads or other organs. Some chemotherapeutic agents are themselves carcinogenic. Patients undergoing radiotherapy or chemotherapy must also take precautions to avoid what can be life threatening infections in their therapy-induced immuno-suppressed condition.
Treatments have been developed to counteract the side effects of cancer radiotherapy and chemotherapy. For example, drugs can be administered to provide some relief from nausea, antibiotics can be administered to help fight infection, and transfusions can be administered to increase blood cell and platelet counts if necessary.
In accordance with this invention it has been found that interferon administered in conjunction with cancer therapy is effective to reduce the undesirable side effects of cancer therapy. The effective route of administration is by contact of interferon in relatively low dosages with the patient's oral and pharyngeal mucosa. It is necessary that the interferon be administered in a form adapted to promote contact with the inside of the patient's mouth and throat in amounts effective to reduce the toxic side effects of cancer therapy, including chemotherapy and radiation therapy.